1. Field of the Invention
The present invention relates to novel piperazine derivatives. Further, the invention is concerned with a process for the production of these piperazine derivatives and medicines containing such compounds which are effective to prevent or cure myocardial infarction.
2. Description of the Prior Art
There is a tendency of myocardial infarction-bearing patients increasing as the population of the aged increases. Therefore, the medical prevention and treatment of myocardial infarction are greatly important from a viewpoint of national health protection.
However, myocardial infarction is extremely difficult to medically prevent or treat even with the modern medical science. The presently prevalent approach to the medical prevention and treatment of myocardial infarction is to administer medicines for controlling or curing cardiac insufficiency, arrhythmia or ischemic heart disease which is liable to produce myocardial infarction. This gives an impetus to the development of any medicines effective to medically prevent or treat myocardial infarction.
The present inventors have conducted continuous researches for medicines having superior medicinal activities for the prevention or cure of myocardial infarction. They have synthesized some novel compounds represented by the general formula (1) as will be described later, and as a result, have discovered that these compounds exhibit markedly superior inhibitive activities against myocardial infarction and have a high level of safety. This discovery has led to the present invention.